Machine and method for cladding pipes and the like



April 30, 1957 v. E. KNAPP ETAL MACHINE AND METHOD FOR CLADDING PIPES ANDTHE LIKE Filed June 22, 1954 2 Sheets-Sheet 1 BY di aff rfi/dip 7K ATTORNEY April 30, 1957 v. E. KNAPP ET AL MACHINE AND METHOD FOR CLADDING PIPES AND THE LIKE Filed June 22, 1954 2 Sheets-Sheet 2 zvw @L7M/IWW. m R www .am WY B mi@ Mim the molten material 19,'a guide 17 is provided at the exit 4end of /the bath. This guide is in the form of a tubular member 21 having'ea centrally disposed ilange 22 extending outwardly therefrom, as shown in Fig.y 6. This angeissecured tightly against the end Wall'16'of the trough 11 by agcollarA 24 bolted against a circular flange 25 extending from and formedintegrally with the wall Y16. In order to'prevent leakage of the molten material, a high temperature packing 23 such as asbestos is inserted between theilange 22 and the wallrll.` The inside diameter of the tubular guide 21 determines the thickness of the coating that will form on the pipe 1S while it is within the bath 19. In order to insure a uniform thickness of' the coating about the entire periphery of the pipe, a plurality of ribs 26 of relatively thin` section are providedfwhich ride on and center the pipe 15 within the tubularV member 21. The ribs are disposed substantially wholly within the bath lil so that the molten material will tlow` around the ribs as the pipe i passes l therethrough to form a uniform and continuous coating completely about the'pipe and without any evidence in the form of a longitudinal seam or ygroove evidencing the use of ribs. A i

As the pipe with the cladding 15 leaves the guide 17, it passes through a water jacket assembly 28 accurately aligned with the guide tube 21 and surrounded by an outer jacket 29, as shown in Fig. 2. This outer jacket 29v is Vessentially cylindrical in shape and is provided with a flanged end part 31 secured to the end wall 16 of the bath 10 by means of a disc 32 interposed therebetween. This disc has a central opening 33 surrounding the flange extending 'from the end wall 15`of the bath 10 and is fastened to the'end wall 16 of the bath by bolts 34 and to the flange 31 by bolts 34V so that the bath 1l) and the housing 29 provide Va substantially unitary structure.

The cooling jacket 2S isl cylindrical in shape and has an `inner wall 35immediately surrounding the `pipe 15 and an outer wall 36 which is spaced from the inner wall to provide a circular channel 37 for the circulation of water. The inner and outer walls of this jacket are connectedby a pair of end anges 38 and39 which completely seal channel 37. The flange 38 is bolted to a flange 49 that may be formed integrally with the righthand end of the guide tube V21 as shown in Fig. 2 so Vthat the cooling jacket 2S is accurately aligned with and in Y effect forms' `part of the guiding tube 21. To effectively align the cooling jacket Yand guiding tube with the entrance opening 14 in the bath 1G, three bolts 4l areprovided which are secured at intervals of l2() degrees to the flange 39 of the water jacket 2S and extend outwardly through the wall of the outer housing y29,V as shown i'nAFig. 4. By the` adjustment of the nuts 42 cooperat- 4 all portions of the coating are subjected substantially equally to this smoothing pressure.A

More specifically, the upper rollers of the pairs -47 inclusive are carried in a rectangular bracket member and journaled to the side walls 51 and 52 by transverse axles 53, as shown in Fig. 5. The rectangular `member 50 is Supported within the outer housing 29 by a pair of lead screws S4 and 55 that threadably engage the Wall 0f the housing 29'and are rotatably secured to the end walls 56 and 57 thereof. The lead screws 54 and are each provided with hand wheels 54 and 55' for adjusting the rollers toward and away from the pipe 15 to eiect the desired pressure on the coating 1S. The lower rollers 45 to 47 inclusive are similarly supported within a rectangular bracket member 58 adjustably mounted on the housing 29 by` a pair of lead screws 59 and 6?. The transverse or horizontal rollers 48 and 49 are supported and mountedin the same manner as the vertically disposed rollers described above and are adjustable by four lead screws of which only two are shown in Fig. 5, namely, lead screws 61 and 62. With this arrangement the horizontal and vertical roller assemblies may be adjusted relative to the pipe 15 to accurately align'them with the opening in the jacket 2S and the entrance opening 14 in the bath lll. The rollers function to smooth all imperfections and distortions that may be in the coating after it leaves the cooling apparatus 28 and provides a smooth, homogeneous and uniing with these bolts 41, accurate and precise alignment of thecooling jacket and the lguiding tube 21 can bel secured. While anyfsuitable cooling medium may be circulated through the opening 37 inthe jacket 2S, 'it has been found a controlled stream of water will suffice and effect suiiicient cooling of the coating 1S to permit the desired smoothing Aoperation that is to beefected by the pressure roller assembly 30 alsodisposed within the housing29. For this purpose a pair of uid connectors 43 and 44 are provided which communicate withoppo- 'site 4portions of the opennig 37 and provide for the uniform flow offcooling water through the jacket.

After lthev coating has been cooled by `passage through the jacket 28, the pipe enters the roller assembly 30 which includes three .pairs of rollers 45, V,46 and 47 disposed in a verticalplane and two pairs of rollers 48 and 49 disposed in a horizontal plane.VV Each of these rollers are provided with a concaverouter surface havform coating without entailing the expense of complicated and expensive equipment. 'At the same time, a firm mechanical bond as Well as a chemical bond is secured.

In order to feed the pipe 15'uniforrnly through the machine, any suitable conveyor means may be employed, such as a link chain 64 and cooperating supporting sprockets 65. With the use of a chain 64, as the translating means, a clamp 66 having a clamping screw 67 is secured about the pipe and coupled with the chain by a link 68 pivotally connected to the clamp 66 and having a hook 69 formed on the outer end thereof for engagement with the chain 64. This translating means provides a simple and Aeffective method of pulling the pipe, since the clamp 66 contacts a substantial area of the pipe and will therefore not materially injure or damage the coating 15'. At the same time, the clamp can be readily and easilyf loosened and slipped rearwardly of the pipe each time the link member 68 arrives at a point near the end of the conveyor system and littletime is lost in repositioning the clamp 66 to feed through another section ofthe pipe to be coated. In addition, the use of this methodof pulling the pipe through the coating apparatus enables vthe rollers 45 through 49 to be used as smoothing rollers so that longitudinal pressures will not be applied to the coating which may distort it or adversely affect its bond with the pipe. Y

From the above it is apparent that the illustrated embodiment lof the invention provides a simple, effective and relatively high speed method Vand apparatus for coating or cladding rods, tubing, pipe 'and other similar articles. Furthermore, by reason of the inherent characteristics of this machine embodying ea minimum number of parts, little or no maintenance is required to maintain the equipment in operation and variation in pipe sizes oan readily be accomplished merely be interchanging the pipe guides 17, the jacket 28 and the rollers 45-49 to accommodate the new size of the pipe. i It desired, this `apparatus may also include an annular die 70 positioned ing aradius equal to the desired finished radius of the coating 15' to be applied to the pipe. The horizontal and:` vertical rollers are' alternated and disposed so that moving a small portion of the cladding 1S land thereby v provide more accurate control over -theethickness of ther 1 VWhile only one embodimentof the invention hasbeen sh'own and described, it is apparent that changes, modications and alterations may bemade without departingfrom the true scope and'spirit thereof.V V

Having thus described our invention, we claim:

l. In apparatus for cladding pipe, a trough for holding fluid cladding material comprising an elongated receptacle having front and rear Walls, said front wall having an entrance opening above the level yof said fluid and said rear wall having an exit opening below the level of said uid and means in said exit opening for 'aligning the pipe therein `and for controlling the thickness of said cladding.

2. In apparatus for cladding pipe, a trough for holding a duid cladding material comprising an elongated receptacle having front and rear end walls with the depth of the receptacle being shallower yat the front wall than at the rear wall, said front wall having an entrance opening above the normal level of the uid and said rear wall having `an exi-t opening below the normal level of 'the fluid, and pipe guiding means in said exit opening to control the uniformity and thickness of the cladding applied to the pipe.

3. In apparatus for cladding pipe according to claim 2 wherein said pipe guiding means comprises a tube extending into said uid in alignment with said entrance opening vand having at least three longitudinal ribs of a thickness corresponding to the thickness of the clad to be applied and defining a circular opening of a diameter corresponding to the outside diameter of the pipe to be clad.

4. In apparatus for cladding pipe, a trough for holding a fluid cladding material comprising an elongated receptacle having front and rear end walls with the depth of the receptacle being shallower at the front wall than at the rear wall, said front wall having an entrance opening labove the normal level of the uid and said rear wall having an exit opening below the normal level of the uid, pipe guilding means in said exit opening to control the uniformity and thickness of the cladding applied to the pipe, and a cylindrical cooling jacket axially aligned with and coupled to said guiding means for hardening the clad |after passage through said guiding means.

5. In apparatus according to claim 4 wherein said pipe guiding means comprises a tube extending on 'one end into said fluid in alignment with said entrance opening and on the other end to a point spaced from said rear Wall, said other end of said guide being iixedly connected to and in alignment with said jacket.

6. In apparatus for cladding pipe, a trough for holding a fluid cladding material comprising an elongated receptacle having front and rear end walls with fthe depth of the receptacle being shallower at the front wall than at the rear wall, said front wall having an entrance opening above the normal level of the fluid and said rear wall having an exit opening below the normal level of the uid, pipe guiding means in said exit opening to control the uniformity and thickness of the cladding applied to the pipe, a cylindrical cooling jacket axially aligned with and coupled to said guiding means for hardening the clad after passage through said guiding means, and at least four pressure rollers spaced approximately 90 one from the 'other and in line with said guide, said roll-ers forcibly engaging said cladded pipe to smooth the surface of theV clad and removey imperfections therefrom.

7. Apparatus for cladding pipe comprising an elongated trough having front and rear walls for holding a fluid cladding material, said front wall having an entrance opening above the normal level of said iluid and said rear wall having an exit opening below the normal level ot' said uid, tubular pipe guiding means in said exit openling extending on one end into said trough in alignment with said entrance opening and on the other end to a point spaced from said rear wall, a housing secured to said Wall and extending therefrom, a cooling jacket having a central pipe receiving opening secured to said other end ofthe guiding means, means between said jacket and said housing for aligning s'aifd jacket and guiding means with said entrance opening, and a plurality of concave pressure rollers adjustably mounted within said housing and in lali-gnment with said guiding means and cooling jacket for engaging the cladded pipe to smooth the surface thereof.

8. Apparatus according to claim 7 wherein means are provided for forcibly pulling said pipe through said fluid, cooling jacket and pressure rollers.

9. Apparatus according to claim 7 wherein said pressure rollers are arranged in pairs alternately disposed in vertical and horizontal planes.

10. Apparatus for cladding pipe comprising la reservoir for cladding material having front and rear walls, an entrance opening in said front Wall above the level of the cladding material and an outlet in said rear wall below the cladding material, said entrance opening and said outlet being in axilal alignment with each other, and means in said outlet for aligning the pipe therein.

11. Apparatus for cladding pipe comprising a reservoir for cladding material having front and rear walls, said front wall having a pipe inlet above the level of said cladding material and said rear Wall having an outlet therein, means for progressively moving a pipe through said inlet and outlet at an angle with the surface of the cladding material, guide means in said outlet for centering the pipe therein and controlling the thickness of the clad,

f means for cooling the clad, and pressure rollers for smoothing the surface of the clad and removing imperfections therefrom.

References Cited in the le of this patent UNITED STATES PATENTS 112,588 Grey Mar. 14, 1871 610,224 Braddock Sept. 6, 1898 2,353,951 Wood et al. July 18, 1944 2,701,546 Townsend Feb. 8, 1955 

